<!DOCTYPE html>
<html lang="en">
  <head>
    <title>Test::Shadow-DOM inside IFrame</title>
    <meta charset="UTF-8">
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
  </head>
  <iframe height="500" width="300" id="iframe_page" style="border:1px"></iframe>
  <script>
    setTimeout(() => {
      document.querySelector('#iframe_page').src = 'page_with_shadow_dom.html'
    }, 20)
  </script>
</html>
